A123305
Triangle T, read by rows, where column k of T equals (k+1)*(column k of T^2) when shifted to have an initial '1'; i.e., T(n,k) = (k+1)*[T^2](n-1,k) for n>k>=0, with T(n,n)=1 for n>=0.
Original entry on oeis.org
1, 1, 1, 2, 2, 1, 6, 8, 3, 1, 26, 44, 18, 4, 1, 156, 312, 144, 32, 5, 1, 1234, 2776, 1422, 336, 50, 6, 1, 12340, 30312, 16848, 4256, 650, 72, 7, 1, 150994, 397728, 235458, 63072, 10050, 1116, 98, 8, 1, 2204112, 6151768, 3827628, 1076128, 178900, 20376, 1764
Offset: 0
Triangle begins:
1;
1, 1;
2, 2, 1;
6, 8, 3, 1;
26, 44, 18, 4, 1;
156, 312, 144, 32, 5, 1;
1234, 2776, 1422, 336, 50, 6, 1;
12340, 30312, 16848, 4256, 650, 72, 7, 1;
150994, 397728, 235458, 63072, 10050, 1116, 98, 8, 1;
...
Matrix square starts:
1;
2, 1;
6, 4, 1;
26, 22, 6, 1;
156, 156, 48, 8, 1;
1234, 1388, 474, 84, 10, 1;
12340, 15156, 5616, 1064, 130, 12, 1;
...
Note that (column k of T shifted) = (k+1)*(column k of T^2):
k=1: [2,8,44,312,2776,...] = 2*[1,4,22,156,1388,...];
k=2: [3,18,144,1422,16848,....] = 3*[1,6,48,474,5616,...].
-
{T(n, k)=if(n<0||k>n,0,if(n==k,1,(k+1)*sum(j=0, n-1, T(n-1, j)*T(j, k)); ))}
Original entry on oeis.org
1, 1, 2, 6, 26, 156, 1234, 12340, 150994, 2204112, 37617314, 738465620, 16451763834, 411281292920, 11427727238034, 350040470610996, 11736423864328466, 428080429306305136, 16893650334361392866
Offset: 0
Original entry on oeis.org
1, 3, 18, 144, 1422, 16848, 235458, 3827628, 71466174, 1515031920, 36091609434, 957367079244, 28050237910926, 901359663633000, 31567805908329330, 1198307340146774844, 49060139971072916142, 2156816501291429473248
Offset: 0
Original entry on oeis.org
1, 4, 32, 336, 4256, 63072, 1076128, 20900032, 457645984, 11201485632, 304074996512, 9089787596288, 297305835048096, 10578368788224320, 407327197600166304, 16894650230806939776, 751638529171350907808
Offset: 0
Original entry on oeis.org
1, 2, 5, 18, 93, 650, 5825, 64486, 858525, 13460814, 244360845, 5063982498, 118379934453, 3090176655290, 89294118056273, 2834776197278278, 98222473389128821, 3693056479700344798, 149906848766779722109
Offset: 0
Original entry on oeis.org
1, 2, 18, 336, 10050, 423576, 23317042, 1595336448, 131036683554, 12595263510000, 1389395816978554, 173214827643727872, 24105386508556401906, 3706800170875348334480, 624528505602985043491650
Offset: 0
A123312
a(n) = A123311(n)/(n+1), where A123311 forms the central terms of triangle A123305.
Original entry on oeis.org
1, 1, 6, 84, 2010, 70596, 3331006, 199417056, 14559631506, 1259526351000, 126308710634414, 14434568970310656, 1854260500658184762, 264771440776810595320, 41635233706865669566110
Offset: 0
Showing 1-7 of 7 results.
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